doc: add minimal Sphinx setup

Add a minimal Sphinx-based setup, also configuring intersphinx for
Zephyr.

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>

doc/Makefile

@@ -0,0 +1,20 @@
+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line, and also
+# from the environment for the first two.
+SPHINXOPTS    ?=
+SPHINXBUILD   ?= sphinx-build
+SOURCEDIR     = .
+BUILDDIR      = _build_sphinx
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

doc/conf.py

@@ -0,0 +1,32 @@
+# Configuration file for the Sphinx documentation builder.
+#
+# For the full list of built-in configuration values, see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+
+# -- Project information -----------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
+
+project = 'Example Application'
+copyright = '2024, The Zephyr Community'
+author = 'The Zephyr Community'
+release = '1.0.0'
+
+# -- General configuration ---------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
+
+extensions = ['sphinx.ext.intersphinx']
+
+templates_path = ['_templates']
+exclude_patterns = ['_build_sphinx', 'Thumbs.db', '.DS_Store']
+
+
+
+# -- Options for HTML output -------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
+
+html_theme = 'alabaster'
+
+# -- Options for Intersphinx -------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/extensions/intersphinx.html
+
+intersphinx_mapping = {'zephyr': ('https://docs.zephyrproject.org/latest/', None)}

doc/index.rst

@@ -0,0 +1,21 @@
+.. Example Application documentation master file, created by
+   sphinx-quickstart on Wed Apr  3 15:28:39 2024.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+Welcome to Example Application's documentation!
+===============================================
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Contents:
+
+This is a simple Sphinx documentation setup for ``example-application``. You can
+reference Zephyr documentation items, like
+:external+zephyr:ref:`getting_started` or :external+zephyr:c:func:`k_sleep`.
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`search`

doc/make.bat

@@ -0,0 +1,35 @@
+@ECHO OFF
+
+pushd %~dp0
+
+REM Command file for Sphinx documentation
+
+if "%SPHINXBUILD%" == "" (
+	set SPHINXBUILD=sphinx-build
+)
+set SOURCEDIR=.
+set BUILDDIR=_build_sphinx
+
+%SPHINXBUILD% >NUL 2>NUL
+if errorlevel 9009 (
+	echo.
+	echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
+	echo.installed, then set the SPHINXBUILD environment variable to point
+	echo.to the full path of the 'sphinx-build' executable. Alternatively you
+	echo.may add the Sphinx directory to PATH.
+	echo.
+	echo.If you don't have Sphinx installed, grab it from
+	echo.https://www.sphinx-doc.org/
+	exit /b 1
+)
+
+if "%1" == "" goto help
+
+%SPHINXBUILD% -M %1 %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+goto end
+
+:help
+%SPHINXBUILD% -M help %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+
+:end
+popd

doc/requirements.txt

@@ -0,0 +1 @@
+Sphinx